Samuel k



PafentedY Jian. `29, 1884.

('No Model.) V

K.-& J. B.4 DUPP.

PIPE LIPTER FOR 0IL WELVLS.

sAMUEL K. DUEE, or ALLEGHENY, AND JAMEs n; DEEE, E

MTE-n STATES FFM- Assrenons rro rrHE DUEEMAUEACTUEING-oo'MiANnuqLnu-rrna) -'GF rrrrsBUEG, rENNsYLvANrA.

`SPECIFICATION forming lpart of'ietters Patent No. 292,630, datedJanuary 29, 1884-.

Application filed October 15, 1883. (No model.) I

To all whom it may concern-.-

Be it known that we, SAMUEL K. DUFF and JAMEsB. DUEE, citizens of theUnited States,

residing at -Allegheny andPittsburg, in the county of Allegheny andState of Pennsylvaro drawing.

.Our invention relates to an improvement in pipe-lifters; and 1tconsists, first, in the comblnatlon of a hollow cylinder, a hollowliftingscrew having a cylinder formed on its top, and` a suitable nutwhich is applied to the upper end of the pipe which is to be raisedupward; second, in the combination of a lifting-jack or other operatingmechanism, which is provided with a male thread on-its upper side and afemale thread formed in its upper end, with a hollow screw, which isprovided with a male thread, and which passes down'through the top ofthe jack or operating mechanism, and which hollow screw-has a cylinderformed upon its top, in which the nut'which is to be applied to theupper end of thepipe is dropped,

all of which will be more fully described here` inafter.

The object of our invention is to provide a 3o means by which pipes inoil-'wells can be raised upward by means of a lifting-jack orV othersimilar operating mechanism.

The accompanying drawing represents a vertical section of a pipe-lifterembodying our 3 5 invention.

A represents the upper part of a lifting-jack, vof which c is theinnermost vand Z the outer screw, both being at their lowest station.The part marked a is a hollow cylinder attached to 4o or cast on top ofthe screw c, which screw is made hollow and raised or lowered when theratchet (notshown) onthe jack is operated. The

inside of the cylinder (thas outwardly-inclinin g walls a, with shouldere at the bottom. The

4 5 shoulder serves to support four pieces, b, of a vertically-quarteredcircular nut, the outsides ot' which agree with the inclined wall of the1 'The upper end of the pipe P, to be lifted from out a hole in theground, is introduced through the lower end of the hollow screw c of thejack into the cylinder a, and the pieces b, in the form of a nut, laidaround it, their in'- ner threaded faces in contact with the pipe. If,now, the ratchet on the jack be operated to raise the screws ofthe jack,and with it the cylinder a, the pipe P resists the upward movement, andtherebyy causes the pieces b to closeon it, and with their threadedsides to obtain a iirm hold or grip on the pipe. The

`outer form of the pieces b prevents them from sliding` down in thecylinder; butif theyshould,

by accident, sli de, the shoulder e would supp ort them. The piecesbbeing raised with the cylinder a by the screw c of the j ack, the pipelield between the pieces is drawn up with them to a height the screw mayattain. Then arrived at this point, the action of the ratchet is to bereversed, whereby the screws of the jack are lowered. The pipe while thescrews are lowering, being held by the earth surrounding it, remainsstationary, and thereby causes the descendin g pieces b to be slightlylifted up,where by they lose their hold and slide down without changingtheir positions around thepipe. If again raised` by the ratchet, thehold of the pieces b on the pipe is instantly renewed at a distancebelow their former grip equal to the difference between -the lowest andhighest points of the top of the screw c. The operation of raising andlowering the screws in the jack has to be repeated as many times as therising number of feet of the inner screw is contained in the number offeet of length of the pipe;

Having thus described our invention, we claiml. In a device for liftingpipes, the combination of a hollow liftingscrew, provided with a hollowcylinder upon its upper end,

wit-h :u1 ope ating jack 01' mechanism for mising the hollow screwupward7 substan/tially as shown. f H1 2. In :L device for/lftiiligpipes, the combination of a hol'llofwsciew having a Cylinder formedupon'i'fs. top7 the jack A, and the nut B, which 17s applied to theupper end of the PPC USG- ol' the cylinder7 substantially as; EWtloltll. I/

In testimony whereof we affix oui' signatures 1 presence of twowitnesses.

SAM. K. DUFF. JAMES B. DUFF.

fitnessegz l. H. HERRON, T. LEHMANN.

